Tenon's capsule

Tenon's Capsule is a thin membrane that envelops the human eye from the cornea to the optic nerve, serving as a protective layer. It is named after French surgeon Jules Germain Cloquet, who first described it in 1805.

Anatomy

Tenon's Capsule is a fibrous layer that forms the outermost coating of the eyeball, excluding the cornea. It is continuous with the conjunctiva at the corneoscleral junction, also known as the limbus. The capsule is firmly attached to the sclera, the white part of the eye, and loosely connected to the underlying choroid and retina.

The posterior part of Tenon's Capsule is pierced by the optic nerve and is continuous with the dura mater, one of the meningeal layers covering the brain and spinal cord. The anterior part of the capsule forms a socket in which the eyeball moves. This socket is lined by the extraocular muscles, which control eye movement.

Function

The primary function of Tenon's Capsule is to protect the eye from injury and infection. It acts as a barrier against the spread of infections from the external environment to the inner parts of the eye. The capsule also provides a smooth surface for the movement of the eyeball and extraocular muscles.

Clinical Significance

In ophthalmic surgery, Tenon's Capsule plays a crucial role. It is often incised in procedures such as strabismus surgery and glaucoma surgery. The capsule can also be affected by diseases such as idiopathic orbital inflammatory syndrome, where it becomes inflamed, and Tenon's capsule cyst, a rare condition where a cyst forms in the capsule.

See Also

• Eye anatomy
• Ophthalmology
• Strabismus
• Glaucoma